(a) Field of the Invention
The present invention relates to an oil supply structure of a continuously variable valve timing (CVVT) apparatus, and a cylinder head employing such an oil supply structure.
(b) Description of the Related Art
Optimal operation of intake and exhaust valves depends on rotation speed of the engine. That is, optimal opening/closing timing, and optimal lift, of the valves depends on the rotation speed. A continuously variable valve timing (CVVT) apparatus enables different valve timings depending on the engine speed. Typically, a CVVT apparatus is operated by oil hydraulic pressure, and its precision can be improved by removing impurities from the oil.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.